A conventional in the ear (ITE) or completely-in-the-canal (CIC) hearing aid has a shell that is individually custom manufactured to fit precisely in the ear canal of the user so that the shell can be retained securely in its intended position in the ear canal. The shell contains the hearing aid components, e.g. electronics, microphone, receiver, battery, etc. Typically, the customized shell is made from solid materials to secure retention of the shell in the ear canal and tightness of the fit.